CN101808674A - Method for Disinfecting Ophthalmic Lenses Using Radiation - Google Patents

Abstract

A method of sterilizing an ophthalmic lens hermetically sealed in its primary packaging comprising shaking said ophthalmic lens and its primary packaging and applying a strength of about 10mW/cm²Of said ophthalmic lens and its primary package. The lens may be immersed in a solution. The material of the lens may be etafilcon A, genfilcon A, galyfilcon A, senofilcon A, lenefilcon A, lotrafilcon A, lotrifilcon B, lotrafilcon A, genfilcon A, galyfilcon B, galyfilcon A, galyfilcon B,balifilcon a and polymacon.

Description

Method for Disinfecting Ophthalmic Lenses Using Radiation

The present invention relates to methods of disinfecting ophthalmic lenses and ophthalmic lenses produced by such methods.

Related Patent Applications

This patent application is a formal application of US Provisional Patent Application No. 61/011,511.

Background technique

Contact lenses that improve vision have been commercially available since the 1950s. The first contact lenses were made of hard materials, and subsequent developments in the field produced soft hydrogel lenses and silicone hydrogel lenses. Ophthalmic lenses are products designed to be inserted into the patient's eye and must therefore be sterilized during their manufacture. Originally steam sterilization was used to sterilize ophthalmic lenses. In this method, an ophthalmic lens immersed in an encapsulating solution is hermetically sealed and held at a certain temperature by heating for a period of time. The lenses, which have been manufactured and placed in packaging with the encapsulating solution, are manually removed from the production line by an operator and placed into a steam sterilizer not connected to the production line. Subsequent developments have resulted in a fully automated process that does not require operators to manually remove the lenses from the production line. Despite the advances, the basic procedure of heating a sealed ophthalmic lens for a period of time (typically to a temperature of about 120° C. to 124° C. for about 18-24 minutes) is still practiced. It would be advantageous to the art if other methods of disinfecting ophthalmic lenses could be discovered. The following invention addresses this need.

Description of drawings

Fig. 1 adopts the disinfection rate comparison after the method of the present invention.

Detailed ways

The present invention includes a method of sterilizing an ophthalmic lens hermetically sealed in a primary package comprising shaking said ophthalmic lens and its primary package and irradiating the ophthalmic lens with a monochromatic ultraviolet light source having an intensity of about 10 mW/ ^cm2 . Ophthalmic lenses and primary packaging thereof.

As used herein, "ophthalmic lens" refers to an ophthalmic device that resides in or on the eye. These devices may provide optical correction or may be cosmetic. The term "lens" includes, but is not limited to, hard and soft contact lenses, intraocular lenses, cover lenses, ophthalmic inserts, and optical inserts. Preferred lenses of the invention are soft contact lenses made from silicone elastomers or hydrogels, including but not limited to silicone hydrogels and fluorohydrogels. Disclosures of soft contact lens formulations are found in the following patents/patent applications: U.S. Patent No. 5,710,302, WO 9421698, EP406161, JP 2000016905, U.S. Patent No. 5,998,498, U.S. Patent Application No. 09/532,943, U.S. Patent No. 6,087,415 , US Patent No. 5,760,100, US Patent No. 5,776,999, US Patent No. 5,789,461, US Patent No. 5,849,811 and US Patent No. 5,965,631. The aforementioned references are hereby incorporated by reference in their entirety. Particularly preferred lenses of the invention are made of etafilcon A, genfilcon A, galyfilcon A, senofilcon A, lenefilcon A, narafilcon A, lotrafilcon A, lotrafilcon B, balifilcon A or polymacon (polymacon). More particularly preferred lenses according to the invention are made of genfilcon A, galyfilcon A, senofilcon A, lenefilcon A, narafilcon A, lotrafilcon A, lotrafilcon B or balifilcon A. Most preferred lenses include, but are not limited to, galyfilcon A, senofilcon A, narafilcon A, U.S. Patent Application No. 60/318,536, entitled "Biomedical Devices Containing Internal wetting Agents," filed September 10, 2001) and its corresponding official U.S. Patent Application Serial No. 10/236,538 (filed September 6, 2002) of the same title, as well as U.S. Patent No. 6,087,415, U.S. Patent No. .5,760,100, US Patent No. 5,776,999, US Patent No. 5,789,461, US Patent No. 5,849,811 and US Patent No. 5,965,631. These patents, as well as all other patents disclosed in this patent application, are hereby incorporated by reference in their entirety.

As used herein, primary package refers to a single lens storage unit commonly referred to as a blister pack. A typical blister pack has a portion containing the lens with or without encapsulating solution and a cover that is hermetically sealed to the lens housing portion. Examples of such primary packaging include, but are not limited to, those disclosed in the following patent publications: U.S. Patent No. D 435,966S, No. 4,691,820, No. The patent is hereby incorporated by reference in its entirety. The cover portion is typically a flexible material (such as an aluminum laminate), however it is preferred that the cover is transparent to the wavelength of the sterilizing radiation material, such as a laminate of various polymers. The preferred housing and cover portions transmit ultraviolet light through these materials to the ophthalmic lens enclosed in the primary packaging. Preferably, at least about 10% to about 100% of the monochromatic ultraviolet light illuminating the primary packaging is transmitted by the primary packaging. The cover and shell portions of the primary package are hermetically sealed using a number of methods, preferably heat sealing.

As used herein, "shaking" means shaking, rotating or otherwise moving the package during illumination of the lens by a monochromatic light source. Preferably the primary package is shaken during irradiation. Particularly preferred are shaker packs.

Monochromatic light sources include, but are not limited to, excimer lamps of a specific intensity. One or more such light sources may be used to increase the intensity of light received by the primary packaging and ophthalmic lens. Preferably, the primary packaging and ophthalmic lenses are exposed to monochromatic ultraviolet light at an intensity of about 10 mW/ ^cm2 to about 1000 mW/ ^cm2 , more preferably a monochromatic ultraviolet light at an intensity of about 50 mW/ ^cm2 to about 300 mW/ ^cm2 ultraviolet light. The preferred wavelength of monochromatic ultraviolet light is about 282 ± 10 nm.

As used herein, an "encapsulating solution" of the present invention may be an aqueous solution. Typical solutions include, but are not limited to, saline solution, other buffers and deionized water. Preferred aqueous solutions are deionized water or saline solutions containing salts including (but not limited to): sodium chloride, sodium borate, sodium phosphate, sodium hydrogen phosphate, sodium dihydrogen phosphate or their corresponding potassium salts. These components are usually combined to form a buffer that includes an acid and its conjugate base such that the addition of the acid and base causes only a relatively small change in pH. The buffer may also include 2-(N-morpholine)ethanesulfonic acid (EMS), sodium hydroxide, 2,2-bis(hydroxymethyl)-2,2',2"-nitrilotriethanol, n - Tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, citric acid, sodium citrate, sodium carbonate, sodium bicarbonate, acetic acid, sodium acetate, ethylenediaminetetraacetic acid, etc. and combinations thereof. Preferably, The solution is borate-buffered or phosphate-buffered saline or deionized water.

In addition, the present invention includes an ophthalmic lens hermetically sealed in a primary package, the lens being manufactured by a process comprising shaking said ophthalmic lens and its primary package and applying monochromatic ultraviolet light at an intensity of about 10 mW/ ^cm A light source illuminates the ophthalmic lens and its primary packaging.

example

Example 1

Senofilcon A lenses were prepared using known methods and placed in polypropylene blister packs with 900 [mu]L borate buffered saline encapsulation. Bacillus pumilus prepared at 10 ⁶ spores/ml was injected into each package. The package is heat-sealed with a transparent high barrier gas barrier film. One set of packages was placed in the radiation chamber and shaken (back and forth at a frequency of 15 Hz and an amplitude of 0.375 inches) while it was exposed to radiation, and the other set of packages was placed in the radiation chamber and shaken without shaking. exposure to radiation. Each set of packages was irradiated with two excimer lamps (one above and one below the package) with a total intensity of radiation reaching the packages of 115 mW/cm ² . The package is irradiated for a period of 4.3 seconds to 87 seconds so that the amount of radiation exposed is a specific value between 0.5 and 10 J/cm ² . After exposure, the packages were analyzed to determine the degree of microbial inactivation, listed as the number of samples with microbial activity compared to the total number of packages tested. Table 1 presents this data. The data indicate that shaking the packages reduces or eliminates microbial activity in the treated packages at each radiation dose level tested.

Table 1. Number of packages showing microbial activity after exposure

Radiation dose (J/cm ² ) no oscillation Oscillation 0.5 37/100 1/100 2.0 15/100 1/100 8.0 3/100 0/100 10.0 1/100 0/100

Example 2

Senofilcon A lenses were prepared, packaged and sealed as in Example 1, except that some packages were injected with Bacillus pumilus prepared at 10 ⁶ spores/ml and others were injected with Bacillus pumilus prepared at 10 ³ spores/ml. Bacillus. During the irradiation, as in Example 1, a part of the injected package was shaken separately. The packages are then analyzed to determine the bacterial count. Figure 1 presents the relevant data. The graph shows that shaking reduces the amount of radiation (mJ/cm ² ) required to sterilize the package.

Claims (12)

1. A method of sterilizing an ophthalmic lens hermetically sealed in its primary packaging, said method comprising shaking said ophthalmic lens and its primary packaging and applying a monochromatic ultraviolet light source with an intensity of about 10 mW/ ^cm2 The ophthalmic lens and its primary packaging are irradiated. 2. The method of claim 1, wherein the light source has an intensity of about 10 mW/ ^cm2 to about 1000 mW/ ^cm2 . 3. The method of claim 1, wherein the light source has an intensity of about 50 mW/ ^cm2 to about 300 mW/ ^cm2 . 4. The method of claim 1, wherein the light source has a wavelength of about 282 ± 10 nm. 5. The method of claim 1, wherein the ophthalmic lens and primary packaging thereof further comprises an encapsulation solution. 6. The method of claim 1, wherein the ophthalmic lens is selected from the group consisting of etafilcon A, genfilcon A, galyfilcon A, senofilcon A, lenefilcon A, lotrfilcon A, lotrifilcon B, balifilcon A, and polymacon. 7. An ophthalmic lens hermetically sealed in its primary packaging, said ophthalmic lens being manufactured by shaking said ophthalmic lens and its primary packaging with ^a monochromatic ultraviolet light source having an intensity of about 10 mW/cm The ophthalmic lens and its primary packaging are irradiated. 8. The ophthalmic lens of claim 7, wherein the light source has an intensity of from about 10 mW/ ^cm2 to about 1000 mW/ ^cm2 . 9. The ophthalmic lens of claim 7, wherein the light source has an intensity of about 50 mW/ ^cm2 to about 300 mW/ ^cm2 . 10. The ophthalmic lens of claim 7, wherein the light source has a wavelength of about 282 ± 10 nm. 11. The ophthalmic lens of claim 7, wherein the ophthalmic lens and its primary packaging further comprise an encapsulating solution. 12. The ophthalmic lens of claim 7, wherein said ophthalmic lens is selected from the group consisting of etafilcon A, genfilcon A, galifilcon A, senofilcon A, lenefilcon A, lotrfilcon A, lotrifilcon B, balifilcon A, and polymacon.

Images